Basic polymethine dyestuffs



United States Patentfifice 2,695,289 li sfsdfl V1331 1 5.

2,695,289 BASIC POLYMETHINE DYESTUFFS Werner Miiller, Koln, and can Barres, Leverkusen-Wiesdorf, Germany, assrgnors to Farbenfabriken Bayer Aktiengesellschaft, Leverkusen, Germany, a corporany No Drawing Application Febiimry as, 1951, Serial No. 213,286 Claims priority, application Germany March 9, 1950 s enemas valuable basic polymethine dyestuffs dyeing neutral red to yellowish red shades. In order to obtain such shades he new dyestulfs can be obtained by condensing in own manner N-alkylcarbazole-3- or -6-aldehydes or N-alkylcarbazole-3,6-dialdehydes with one or two moles as the case may be-of ot-methylindolines.

The N-alkylcarbazole aldehydes used in this process can be obtained by known processes, e. g. described by Vilsmeier and Haak in Berichte der Deutschen Chemheir fatty acid salts can be used with great advantage in the various specific fields of application.

The f owing examples illustrate the mventron, With 19, or 1n German Patentsout, however, restricting it thereto, the parts being by I weight: I

p I Example 1 169 parts'of phosphorus oxychloride are, run into a V solution of 446 parts of N-ethylcarbazole-3-aldehyde and 4 parts of l,3,3-trimethyl-2-methylene indoline in 1000 parts of o-dichlorobenzene at a temperature of 70-75 C. 0 minutes to C Thereafter the reaction mixture is poured into water, and

by means of steam.- n cooling the dyestufi solidifies to a crystalline sub- C CH:

and dyes acetate rayon in pure, very clear r-ed tints of good fastness properties.

he N-ethylcarbazole-3-aldehyde is prepared after the method of Viismeier and Haak. It melts ture of 88 C. I care is taken for a good agitation, the

In the same manner also substituted 1,3,3-trirnethylbe condensed with N-alkylcarbazole aldehydes to dyestuifs. y condensing, for instance, N-ethylcarbaZ0le-3-aldehyde with p-chloroor p-methoxy-l,3, -trimethyl-2-methylene indoline, dyestuffs of equally good propertles are obtained being slightly redder than the unsubstituted dyestutf.

Example 2 By condensing N-ethylcarbazole-S,6-dialdehyde with 2 mols of l,3,3-trimethyl-2-methylene indoline, a dye acid somewhat redder than the corresponding dyestuif from N-ethylcarbazole-3-aldehyde (cf. Example 1).

The N-ethylcarbazole-3,6-dialdehyde is obtained by the action of an excess of a mixture of N-methylformanilide and phosphorus oxychloride on N-ethylcarbazole at a temperature of about 65 C. It melts at 172 C.

1. New basic polymethine dyestuffs of the general formula I hydrogen, halogen, NO2, alkyl, and alkoxy, at least one being said radical; R1, R2, and alk stand for lower alkyl radicals.

2,695,289 Th n ew basic pciymethinc riycs tufi ofihcfcrnmla; v S. f 1'he new basicyciymethine dyestuif of the formula: H3O on, H CH: E10 CE: w a 0 O c 1 a 5 CH=OH-C c-ca=on omen-c N N N N N 2 G 10 H30 A0 3 Ac CH3 2H5 2115 in which Ac stands for an acid radical. in which Ac stands for an acid radical.

3. The new basic polymcthinc dyestufl of the formula:

H30 References Cited in the file of this patent UNITED STATES PATENTS i 01 Number Name Date OH=OH-C 2,028,141 Ackerman Jan. 2, 1936 j FOREIGN PATENTS N Number Country Date 469,748 Great Britain 1937 nHs in which Ac stands for an acid radical.

ethine dyest 4. The new basic polym ufi of the fcrmuia: 25 

1. NEW BASIC POLYMETHINE DYESTUFFS OF THE GENERAL FORMULA 